44 



Biological Chemistry. 



and glass beads are introduced through the side tube till 

 the bulb of the thermometer is nearly covered. Tube A 

 is then inserted into a jacket of special form (B, see illus- 

 tration), which also carries a side tube for the insertion of 

 a condenser ; into this jacket some of the solvent is intro- 

 duced. The whole is then placed on an asbestos place 



Fig. 17. 



carrying funnels, and is gradually heated by Bunsen 

 burners, which are not placed directly below the glass 

 apparatus. The object of the glass beads and jacket B is 

 to ensure regular ebullition and to prevent loss of heat by 

 radiation. After the liquid has been in a state of regular 

 ebullition for about five minutes, the position of the 



